Hyperlinks in outlook

I ran into a very similar sounding problem with Outlook 2k and Lotus Notes Doclinks, The culprit was an Outlook security update that was stopping all such things (docinks, hyperlinks and what have you) Since Microsoft provided no configuration options, i had to remove office, and re-install, and not use their security update. ( which was downloadable as it's own entity, but was also integrated in sp2, so we had to leave it at sp1-a)

If it is not hat problem, then it likely is just an associations problem, you may need to associate hyperlinks with IE or netscape, according to preference.